Crutchfield Customer Review (What's this?)
I installed these baffles in the rear deck of my car when I was installing new speakers in my doors and rear deck. I didn't realize it while driving but my passengers couldn't hear a thing while sitting in the back! I ended up having to fade a decent amount to the front because the baffles were enhancing the sound so much since I didn't use them in my doors.
Pros: Reduces sound and bass loss greatly! Easy to install, flexible, and easily can poke holes through it.
Cons: None, they work as advertised.